Also known as USGS 14023

Where: Nuevo Leon, Mexico (25.8° N, 99.2° W: paleocoordinates 26.6° N, 93.1° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Upper marine sandstone Member, Early/Lower Oligocene (33.9 - 28.4 Ma)

• Lower Oligocene age faunas in notheastern Mexico are closely allied to the Chickasawhay and Suwanee limestones of the eastern Gulf Coast. They are recognised in a lower marine sandstone, presumably of lower Oligocene age, and in an upper marine sandstone, presumably of middle Oligocene age. The marine beds are separated by non-maine sediments, typically red and green bentonitic clays. The Oligocene series in Mexico is measured in thousands of feet, although the fauna is only known from a few isolated outcrops.

• bed-level stratigraphic resolution

Environment/lithology: estuary or bay; lithified, concretionary, silty, conglomeratic, calcareous, cherty/siliceous sandstone

Size class: macrofossils

Preservation: replaced with silica

Reposited in the USNM

Collection methods: quarrying,

• Collections reposited in USGS and USNM collections.

Primary reference: J. Gardner. 1945. Mollusca of the Tertiary formations of Northeastern Mexico. Geological Society of American Memoir 11 [M. Kosnik/M. Kosnik/M. Kosnik]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 43080: authorized by Austin Hendy, entered by Austin Hendy on 10.08.2004

Creative Commons license: CC BY (attribution)